7 Reasons Why Your Windows Are Leaking

February 21, 2022



Reasons For Window Leaking - Clera Windows + Doors

In homes with windows that have been in place for more than 30 years, leaky windows is not unusual. When you have windows leaking, whether it’s because of wear and tear or poor window installation, you will face issues such as:

Oftentimes, if you have old windows that are leaking, the most cost-effective and long-lasting solution would be to get replacement windows from a trusted window manufacturer. Choosing a window manufacturer like Clera Windows + Doors will also give you the assurance of receiving high-quality windows with a comprehensive lifetime warranty.

However, before investing in new windows, you may be curious why you have windows leaking in the first place. In this article, we explore the most common causes of leaky windows.

Let’s begin!

Reasons Why Your Windows Are Leaking - Clera Windows + Doors

1. It’s Not a Leak, It’s Condensation

Not all kinds of condensation is bad. In fact, condensation happening on the exterior side of the window during the summer season is a sign that the window is insulating your home well. We discuss the details of this phenomenon further in our article, “Is Window Condensation a Bad Thing?”  

However, the type of window condensation that is most commonly mistaken for windows leaking is condensation on the interior. Contrary to what it looks like, this is NOT a definitive sign that your window is leaking. This, instead, points to high humidity in your home.

This is common during the winter because condensation forms on glass when the glass is cooler than the moist warm air that touches it. As more condensation forms, this can drip and accumulate on your window sill or drip along the walls – thereby resembling a window leak.

Though the root cause of interior window condensation is not your windows leaking, high humidity may cause issues down the line. If your home’s humidity is too high, it can encourage the proliferation of mould, make wood swell and warp, and speed up corrosion of metallic components.

2. A Broken Window Seal

Through time, window seals can break. This is usually due to wear and tear. Broken window seals can be a result of the following:

  • Cracked caulking; and/or
  • Flattened or worn out weatherstripping.

Cracked caulking or failing weatherstripping can cause air leaks and heat loss. Furthermore, when such window seals are broken, they can allow rainwater to seep into the house. Fortunately, these issues can be fixed easily. See how in our article on “How to Repair a Broken Seal on a Window.”

3. Inadequate Window Installation

No matter how good your replacement windows are, proper installation is required for you to avoid windows leaking. Therefore, make sure that the contractor installing your windows is properly trained for the job.

For window companies like Clera Windows + Doors, you won’t even need to look for a contractor to install your window. We offer professional window installation to make sure you get the most from our energy-efficient windows.

4. Intricate Window Layouts Without The Right Protection

There are many different window styles, including unconventional ones such as specialty shaped windows, bay and bow windows, and tall windows. While these styles offer numerous aesthetic and functional benefits, they should be properly installed with the necessary sealants, flashings, or overhangs to prevent water penetration.

These windows are more exposed to the elements than standard windows and extra insulation and protection is necessary to keep wind-driven rainwater from pushing through.

Intricate Window Layouts - Clera Windows + Doors

5. Worn Out Glass Seal

Condensation is a different story when it starts collecting in between panes of glass. This could happen to multi-glazed windows and it’s a clear sign that the seal is broken. Double-glazed and triple-glazed windows have what’s called a sealed glass unit. If the seal is broken for this kind of window glass, condensation can form inside. This means that air leaks are probable.

Furthermore, if in-between condensation is accompanied by small puddles of water forming at the base of the windowsill, it means that rainwater can work its way through the broken seal. The only way to fix this kind of problem is to have the sealed glass unit replaced or to get replacement windows.

6. Poor Flash Installation

In some cases, stains that form at the top of the window frame could actually not be window leaks but leaks in the wall due to poorly installed flashing. To prevent water from penetrating the walls, it is necessary to have solid integration between the window, building paper, and flashing.

Poorly installed or damaged flashing could result in breaks in its surface that allow water to seep through. This problem can be corrected by installing stretchable flashing as a single continuous piece rather than patches that create weak points.

It is important that you don’t substitute the window flashing material with building paper or house wrap. Using the right material ensures superior water protection and reduces the risk of damage caused by leaky windows.

7. No Paint Seal

The exterior moulding that keeps the window in place should be painted in such a way that the paint slightly overlaps onto the pane. This looks like an unusual rule considering that every effort is made to prevent paint from getting on the glass.

However, creating a continuous membrane of paint from the moulding onto the pane forms a waterproof seal to prevent moisture from getting through.

Prevent Windows Leaks with High-Quality Windows

The first step to preventing windows leaking is to make sure that you’re getting your windows from a trusted source like Clera Windows + Doors. Over the past 41+ years, we have transformed hundreds of homes with high-quality windows and doors.

The durability and energy-efficiency of our windows goes hand-in-hand with their leak-resistant properties. Look forward to superior insulation from the elements and stylish window designs!

If you would like to learn more about how we can help you prevent issues of windows leaking, contact us today and get a FREE home consultation!

Related Articles